Search results
Results from the WOW.Com Content Network
Z-parameters are also known as open-circuit impedance parameters as they are calculated under open circuit conditions. i.e., I x =0, where x=1,2 refer to input and output currents flowing through the ports (of a two-port network in this case) respectively.
Applying the transmission line model based on the telegrapher's equations as derived below, [1] [2] the general expression for the characteristic impedance of a transmission line is: = + + where R {\displaystyle R} is the resistance per unit length, considering the two conductors to be in series ,
Equivalent circuit of an unbalanced transmission line (such as coaxial cable) where: 2/Z o is the trans-admittance of VCCS (Voltage Controlled Current Source), x is the length of transmission line, Z(s) ≡ Z o (s) is the characteristic impedance, T(s) is the propagation function, γ(s) is the propagation "constant", s ≡ j ω, and j 2 ≡ −1.
Equivalent circuit of a transmission line for the calculation of Z 0 from the primary line constants. The characteristic impedance of a transmission line, , is defined as the impedance looking into an infinitely long line. Such a line will never return a reflection since the incident wave will never reach the end to be reflected.
L networks for narrowband matching a source or load impedance Z to a transmission line with characteristic impedance Z 0. X and B may each be either positive (inductor) or negative (capacitor). If Z/Z 0 is inside the 1+jx circle on the Smith chart (i.e. if Re(Z/Z 0)>1), network (a) can be used; otherwise network (b) can be used. [2]
In telecommunications and transmission line theory, the reflection coefficient is the ratio of the complex amplitude of the reflected wave to that of the incident wave. The voltage and current at any point along a transmission line can always be resolved into forward and reflected traveling waves given a specified reference impedance Z 0.
This reflects the fact that open circuit (Z=∞) is dual to short circuit (Z=0). A transmission line that is terminated in some impedance, Z L, that is different from the characteristic impedance, Z 0, will result in a wave being reflected from the termination back to the source. At the input to the line the reflected voltage adds to the ...
If the transmission line is uniform along its length, then its behaviour is largely described by two parameters called characteristic impedance, symbol Z 0 and propagation delay, symbol . Z 0 is the ratio of the complex voltage of a given wave to the complex current of the same wave at any point on the line.